Read the assertion and reason carefully to mark the correct option out of the options given below : Assertion : When a finely divided active carbon or clay is stirred into a dilute solution of a dye, the intensity of colour in the solution is decreased. Reason : The dye is adsorbed on the solid surface.

• A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
• B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
• C. If assertion is true but reason is false.
• D. If the assertion and reason both are false.
• E. If assertion is false but reason is true.